Research On Synthesing Polybutadiene With Doped Ni-Catalyst System

In the paper, the reaction among different ArOH with different structure, ROH and(i-Bu)₃Al was investigated. Compared to Ni(naph)₂-(i-Bu)₃Al-BF₃·OEt₂ catalystsystem, the capability of catalyst in this catalyst system increased. The effect of ArOHwith different structure on the rule of polymerization was studied. It was found that theeffect of -OAr with different structure on conversion was different, the conversion washighest, when the complex solution made by phenol and ROH with Al was used topolymerization.The effect of temperature, time, Al/B(molar ratio), Al/Ni(molar ratio), Ni/Bd(molarratio), [Bd]₀ on polymerization, the content of gel and microstructure of polymer wasinvestigated in Ni(naph)₂-(i-Bu)₂AlOC₆H₄CH₃-(i-Bu)₂AlOR-BF₃OEt₂ catalyst system.It was found that the content of cis-1, 4-unit was higher, which was over 95ï¼…, and thecontent of gel was lower.When the reaction among phenol, ROH and (i-Bu)₃Al was done, with differentmolar ratio between phenol and (i-Bu)₃Al, and the same molar ratio between phenol andROH, the effect of temperature, time, Al/B(molar ratio), Al/Ni(molar ratio),phenol/Al(molar ratio), Ni/Bd(molar ratio)on polymerization was investigated. It wasfound that the polymerization activity was higher, while phenol/Al(molar ratio) waslittle; the range of Al/B(molar ratio) did not become narrow, when phenol/Al(molar ratio)reduced. The effect of Al/B(molar ratio), Al/Ni(molar ratio)on conversion was same tothe effect of Ni(naph)₂-(i-Bu)₂AlOC₆H₄CH₃-(i-Bu)₂AlOR-BF₃.OEt₂ catalystsystem,and the proper range of Al/B(molar ratio)and Al/Ni(molar ratio) became broader.After B-component modified by phenol and ROH, the effect of temperature,Al/B(molar ratio), Al/Ni(molar ratio), phenolS(molar ratio), Ni/Bd(molar ratio), time onpolymerization and microstructure of polymer were investigated.It was found that theconversion was higher with broader range of temperature,the range of Al/B(molar ratio)became broader, conversion increased,the range of viscosity became broader, as thephenol/B(molar ratio) increased in proper phenol/B(molar ratio)(≦1.0).It was found that, whether premixing phenol and ROH with A1 or premixingphenol and ROH with B,the content of cis-1, 4 unit of the polymer was higher, and thecontent of gel was little. It did not change the stereospecificity after the phenol andROH joined the reaction.As the effect of time and DP on conversion was investigated. It was found thatwhether premixing phenol and ROH with Al or premixing phenol and ROH withB, They were classified as the fast initiation steady-state step polymerizationprocess. Their kinetic equation was expressed as—d[Bd]/dt=Kpα[Bd][Ni]₀...